On page https://mariadb.com/kb/en/range-partitioning-type/ there is example that leads to error message

ERROR 1364 (HY000): Field 'ip' doesn't have a default value

Suggestion to remove ip and action not null, non-default fields.
Besides that there is a column timestamp with datetime and TIMESTAMP field with insert statement related to later, but with the error message returned for former.

INSERT INTO log(id,timestamp) VALUES 

  (1, '2016-01-01 01:01:01'), 

  (2, '2015-01-01 01:01:01');

This should return error for timestamp type:

ERROR 1526 (HY000): Table has no partition for value 1451606461

instead of datetime type:

ERROR 1526 (HY000): Table has no partition for value 2016

that is returned for other type of insert

INSERT INTO log(id,timestamp) VALUES 

  (1, '2016-01-01'), 

  (2, '2015-01-01');

Maybe to add both tables?